According to Collins-Robert English-French Dictionary by Beryl T. Atkins, Alain Duval, and Rosemary C. Milne, ed. 1985, manufactured in the United States of America by Rand McNally & Company,
(US) God's own country ** les États-Unis
- DESCRIPTIVE LABELS
(**) indicates that the expression is used by some but not all educated speakers in a very relaxed situation. Such words should be handled with extreme care by the nonnative speaker unless they are very fluent in the language and are very sure of their company.
Per Oxford Dictionaries Online:
God's [own] country
An area or region supposedly favored by God, especially the United States regarded in this way.
Example sentences
It is the laxity of the authorities which has led to such a situation in the God's own country.
Visitors sometimes ask if this is supposed to be God's country or something.
Of course, the irony was all the sharper because these events had taken place not simply in God's country, but at summer camp.
My question is, what's the story behind God's [own] country? Is this expression most commonly used among people who believe in God?
In other words, would it sound strange (unusual) or out of place to hear such words coming out of the mouth of a self-declared atheist?
Also, is Collins-Robert's comment fact, that such phrase might be perceived as offensive by some, and as such should be handled with extreme care unless one is very sure of their company?
EDIT:
These are the related explanatory notes to Collins-Robert English-French Dictionary found in the beginning of the book.
(*) indicates that the expression, while not forming part of standard language, is used by all educated speakers in a relaxed situation, but would not be used in a formal essay or letter, or on an occasion when the speaker wishes to impress.
E.g. gobbledygook*; it's a piece of cake* (Brit), it's a walkover*; to make a bolt for it*; he's pretty hot* at football.
(**) indicates that the expression is used by some but not all educated speakers in a very relaxed situation. Such words should be handled with extreme care by the nonnative speaker unless they are very fluent in the language and are very sure of their company.
E.g. to be done**, be taken for a ride**, be had**; bigwig**
(***) means "Danger!" Such words are either "swear words" or highly indecent or offensive expressions which should be avoided by the nonnative speaker.
E.g. to screw***; you bloody fool!***